This invention relates generally to yokes with clamp bolts for securing the yokes on shafts and more particularly to slap yokes, such as are used in vehicle steering columns and other rotary-drive devices, having clamp bolts which not only clamp the yoke to the shaft but also position the shaft within the yoke during clamping.
Rotary shafts are commonly connected using yokes with universal joints to allow for slight and varying misalignments between coupled members. The yokes usually have shaft receiving ends with splines or other non-cylindrical features such as opposed flats to provide rotary drive capability between the shaft and yoke. Slap yokes are often used for such connections. They are made from flat metal plate formed in a U-shaped configuration to provide a socket having holes in its walls for a transverse bolt to provide clamping force to hold the yoke on the shaft. During assembly, the shaft is laid into the socket, pressed against the closed side of the socket, and clamped in place by tightening a bolt inserted through the holes in the walls of the socket. The shaft is also usually formed with an undercut section to coincide with the bolt location and to confine the axial location of the yoke on the shaft within a designed range. It is necessary to force the shaft against the bottom of the U-shaped portion, in order to correctly align the yoke and the shaft. This is usually accomplished by features of the yoke or bolt which provide a radial force against the shaft, from the open side of the U-shaped portion of the yoke, to force the shaft against the closed side.
One approach to radially pressing the shaft against the socket is to provide wedge shaped features at the sides of the yoke which bear against the shaft when the bolt is tightened and force the bolt down against the yoke. Another method employs a nut and a cam bolt which has a single or multi-lobed form along its center and which wedges by cam action against the shaft when torque is applied to the bolt. These and other even more complex methods have been successfully used to provide the required alignment and clamping. All, however, require handling of an excessive number of pieces during installation in close quarters, or they require components which include costly features.
The foregoing illustrates limitations known to exist in present rotary-drive shaft connectors. Therefore, it would be advantageous to provide an alternative directed to overcoming one or more of the limitations set forth above. Accordingly, a suitable alternative is provided including features more fully disclosed hereinafter.